CN108626208B - Kit for mechanically coupling a rod to a ceramic element - Google Patents
Kit for mechanically coupling a rod to a ceramic element Download PDFInfo
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- CN108626208B CN108626208B CN201810225726.3A CN201810225726A CN108626208B CN 108626208 B CN108626208 B CN 108626208B CN 201810225726 A CN201810225726 A CN 201810225726A CN 108626208 B CN108626208 B CN 108626208B
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Images
Classifications
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B1/00—Devices for securing together, or preventing relative movement between, constructional elements or machine parts
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B21/00—Means for preventing relative axial movement of a pin, spigot, shaft or the like and a member surrounding it; Stud-and-socket releasable fastenings
- F16B21/10—Means for preventing relative axial movement of a pin, spigot, shaft or the like and a member surrounding it; Stud-and-socket releasable fastenings by separate parts
- F16B21/16—Means for preventing relative axial movement of a pin, spigot, shaft or the like and a member surrounding it; Stud-and-socket releasable fastenings by separate parts with grooves or notches in the pin or shaft
- F16B21/165—Means for preventing relative axial movement of a pin, spigot, shaft or the like and a member surrounding it; Stud-and-socket releasable fastenings by separate parts with grooves or notches in the pin or shaft with balls or rollers
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D1/00—Couplings for rigidly connecting two coaxial shafts or other movable machine elements
- F16D1/10—Quick-acting couplings in which the parts are connected by simply bringing them together axially
- F16D1/108—Quick-acting couplings in which the parts are connected by simply bringing them together axially having retaining means rotating with the coupling and acting by interengaging parts, i.e. positive coupling
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D11/00—Clutches in which the members have interengaging parts
- F16D11/16—Clutches in which the members have interengaging parts with clutching members movable otherwise than only axially
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16B—DEVICES FOR FASTENING OR SECURING CONSTRUCTIONAL ELEMENTS OR MACHINE PARTS TOGETHER, e.g. NAILS, BOLTS, CIRCLIPS, CLAMPS, CLIPS OR WEDGES; JOINTS OR JOINTING
- F16B2200/00—Constructional details of connections not covered for in other groups of this subclass
- F16B2200/85—Ceramic-to-metal-connections
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- F—MECHANICAL ENGINEERING; LIGHTING; HEATING; WEAPONS; BLASTING
- F16—ENGINEERING ELEMENTS AND UNITS; GENERAL MEASURES FOR PRODUCING AND MAINTAINING EFFECTIVE FUNCTIONING OF MACHINES OR INSTALLATIONS; THERMAL INSULATION IN GENERAL
- F16D—COUPLINGS FOR TRANSMITTING ROTATION; CLUTCHES; BRAKES
- F16D11/00—Clutches in which the members have interengaging parts
- F16D2011/004—Clutches in which the members have interengaging parts using an internal or intermediate axially slidable sleeve, coupling both components together, whereby the intermediate sleeve is arranged internally at least with respect to one of the components
Abstract
A kit for mechanically coupling a ceramic element to a rod, the ceramic element including a cylindrical ceramic bore defined by a cylindrical bore wall including a recess and extending along a longitudinal axis, the rod comprising: an outer tube including an extension adjacent the insertion portion, an outer tube wall, and an outer tube bore; a protruding member insertable into the recess; and an inner mandrel extending along the axis, wherein the insert portion of the outer tube is insertable into the ceramic bore such that the protruding member engages in the recess and such that the protruding portion protrudes from the ceramic element, the inner mandrel is insertable into the bore of the outer tube such that the protruding member is resiliently stabilized in the recess by a stabilizing portion of the inner mandrel, and the rod is thereby mechanically coupled to the ceramic element, wherein the outer tube cannot translate along the longitudinal axis relative to the ceramic bore, the stabilizing portion of the inner mandrel being radially resilient such that the protruding member can be removed from the recess upon application of a force to the outer tube, the force being greater than a predetermined threshold force required to separate the rod from the ceramic element.
Description
Technical Field
The present invention relates to a kit for mechanically coupling a rod to a ceramic element. The rod is mechanically coupled to the ceramic element if the rod is not free to move along its longitudinal axis relative to the ceramic element. In a preferred embodiment, the mechanical coupling also prevents the rod from freely rotating about its longitudinal axis relative to the ceramic element. For example, such embodiments relate to carousel rollers made of ceramic materials used in high temperature applications.
Background
Mechanical coupling between ceramic components and metal parts is often required, especially in high temperature applications. In such applications, ceramic components are typically exposed to higher temperatures than metal parts because of their higher chemical and physical stability at high temperatures. Therefore, the ceramic element is less likely to warp in response to temperature changes. The ceramic material is also less likely to oxidize or flake off on its surfaces exposed to high temperatures.
However, ceramic materials are more difficult to shape into complex geometries than metals and cannot be clamped to other components with too high a stress because of their brittleness. In many applications, the ceramic elements exposed to high temperatures must interact with other components of the assembly, such as with a drive mechanism for translating and/or rotating the ceramic elements. Therefore, a coupling of the ceramic element with a metal rod is usually necessary, said rod allowing, for example, a transmission from the drive mechanism to the ceramic element. The rod can be locked to the ceramic element, thus forming a rigid system, characterized in that, for all the forces applied to the system, no translational and/or rotational movement is possible between the rod and the ceramic element, unless the coupling is broken. Alternatively, the coupling may form an elastic system, characterized in that the metal rod is disengaged from the ceramic element when the force applied to the system reaches a threshold value, and preferably locks again when the force decreases. The elastic system protects the ceramic element from breakage.
Mechanically coupling the metal rod to the ceramic element is not straightforward. On the one hand, the difference in mechanical properties between metal and ceramic materials can lead to stress concentrations that are difficult to withstand, leading to crack formation and fracture of the ceramic element. On the other hand, ceramic materials have a relatively low Coefficient of Thermal Expansion (CTE) compared to that of metals. This is a significant problem for high temperature applications, where the metal rod will expand to a greater extent than the ceramic element when the temperature is raised from room temperature to the operating temperature, or for applications exposed to temperature changes.
Document US5,695,675 discloses a flow plug made of refractory material for controlling the flow of molten metal out of a tundish in a metallurgical plant. The flow damper is connected to a lifting device through an elongated metal rod, and the lifting device is used for vertically lifting and lowering the flow damper. In the arrangement disclosed, the choke is coupled with the metal rod in an ascending translation by means of a blocking element against the wall of the cavity in the choke rod and mechanically coupled with the metal rod in a descending direction by means of a nut screwed onto the threaded portion of the metal rod and tightly resting against the upper end of the choke.
Examples of applications requiring the transmission of torque from a metal rod to a ceramic element can be found in conveying equipment for conveying articles through a furnace, for example for annealing or tempering of glass or heat treatment of thin sheets made of metal or glass. Conveyor belt assemblies are used to transport articles, which include rotating ceramic rollers, at least some of which are motorized. Such roller assemblies typically comprise a number of ceramic rollers, for example made of fused silica, rotatably mounted on a support by means of a metal spindle mechanically coupled at each roller end. The spindles are rotated by a transmission mechanism forming part of the conveyor belt (e.g. by means of a chain or gears) and transmit the rotary motion to the ceramic rollers by virtue of the mechanical coupling between the conveyor belt and the ceramic rollers. The ceramic rollers of the prior art conveying devices are generally provided with through-channels extending from one end to the other along the longitudinal axis of the roller. A metal shaft is introduced and mechanically coupled to the through-channel and the system is mounted on the bracket. The metal shaft is rotationally coupled with the drive mechanism, and the torque of the metal shaft is transmitted to the ceramic roller, thereby driving the rotation of the ceramic roller. However, machining the through-channels along the entire length of the ceramic roller is a delicate process and above all it makes the ceramic roller more susceptible to breakage. The metal shaft introduced into the through-channel of the ceramic roller is exposed to temperatures similar to those of the ceramic element, which limits the applications in which such a system can be implemented and/or requires the use of special-and expensive-high grade metals.
Document EP 1693635 discloses a conveyor belt roller comprising a ceramic reel coupled at one end thereof to a metal cover, wherein a tolerance ring is interposed between the ceramic reel and the metal cover. The mechanical coupling rotation between the ceramic spool and the metal cover is therefore based solely on the friction between the ceramic spool, the tolerance ring and the metal cover. However, if exposed to high temperature gradients, the metal cover and tolerance ring (also made of metal) expand more than the ceramic spool end, resulting in a loose coupling.
US2013/0330120 discloses a locking mechanism between a metal housing and a hollow structure, which uses a rod inside the hollow structure to push a radially protruding member, thereby ensuring the final fixation of the hollow structure to the housing. The rod is radially rigid while ensuring disconnection due to the axial thrust member. These fasteners are parts of agricultural equipment used at room temperature. Such a mechanism is not suitable for use at high temperatures, and the urging member (such as a spring or made of a rubber material) cannot withstand high temperatures. In addition, when ceramic materials are assembled inside metal elements, extra care must be taken to account for the large difference in thermal expansion coefficient between metal and ceramic materials and the poor tensile strength of ceramics.
US5141355 discloses another locking and release mechanism between a cooperating rod and collar. Couplings with radial elasticity can be used to fine-tune the clamping force. The rod is radially rigid and the target application is performed at room temperature.
It is an object of the present invention to provide an arrangement for mechanical coupling between a ceramic element and a metal rod. The mechanical coupling must be at least translationally and preferably rotationally so as to form a rigid system in which the metal rod is locked to the ceramic element, or an elastic system in which the metal rod is reversibly disengaged when the force applied to the system exceeds a threshold value. The mechanical coupling is easy to install and effective over a wide range of application temperatures and does not require through-passages in the ceramic element, but can be applied to ceramic elements provided with blind holes.
Disclosure of Invention
The invention is defined in the appended independent claims. Preferred embodiments are defined in the dependent claims. In particular, the invention relates to a kit for mechanically coupling a ceramic element to a rod comprising an outer surface made of metal, wherein:
(a) the ceramic element comprises a cylindrical ceramic bore defined by a cylindrical bore wall and extending along a longitudinal axis X1, wherein the cylindrical bore wall comprises at least one recess,
and wherein the rod comprises:
(b) an outer tube comprising a protrusion adjacent to the insert, and further comprising:
an outer tube wall made of metal and defining an outer surface of the rod, wherein a portion of the outer tube wall of the insert is cylindrical, extends along a tube axis from a proximal end of the projection to a distal end of the insert, and has a radius R8 mating with the cylindrical ceramic hole,
an outer tube bore, preferably comprising a cylindrical portion of radius R8b, said outer tube bore extending from the proximal end along the tube axis and over the entire length of the protrusion and further over at least a part of the length of the insertion portion,
(c) at least one protruding member comprising a protruding portion having a geometry insertable into at least one recess of the ceramic element,
(d) an inner mandrel extending along an axis and having a radial dimension suitable for insertion into the outer tube bore, and preferably comprising a cylindrical portion having a radius R5 ≦ R8b, wherein
(e) The insertion portion of the outer tube is insertable into the ceramic bore such that the protruding portion of the at least one protruding member engages in the at least one recess and such that the protruding portion protrudes from the ceramic element, and wherein
(f) The inner mandrel being insertable into the outer tube bore from the proximal end of the outer tube such that the protruding portion of the at least one protruding member is elastically stabilized in the at least one recess by the stabilizing portion of the inner mandrel, and the rod is thus mechanically coupled to the ceramic element, characterized in that the outer tube is not translatable along the longitudinal axis b relative to the ceramic bore,
wherein the stabilizing portions of the inner mandrel are radially resilient such that the at least one protruding member is removable from the at least one recess upon application of a force to the outer tube that is greater than a predetermined threshold force required to separate the metal rod from the ceramic element.
This elasticity of the inner mandrel is particularly beneficial for the following applications: wherein torque can be transmitted between the metal rod and the ceramic element and wherein such transmitted torque cannot exceed a given threshold value in order to avoid breaking of the ceramic element. In an advantageous embodiment, the stabilisation part of the inner mandrel may have a geometry defining an elastically deformable structure. The stabilizing portion of the inner mandrel may alternatively or additionally comprise an elastically deformable material.
In an advantageous embodiment, the geometry of the at least one protruding member and the at least one recess is such that when said protruding member engages and is stabilized in the at least one recess, the rod is mechanically coupled to the ceramic element such that the outer tube cannot rotate about the longitudinal axis X1 with respect to the ceramic bore. In this configuration, torque may be transferred from the metal rod to the ceramic element by rotating the outer tube.
In an advantageous embodiment, the rod comprises three or more protruding members, the cylindrical ceramic bore wall comprises three or more recesses, and the projections of the three or more recesses on a transverse plane P1 perpendicular to the longitudinal axis X1 are evenly distributed on the circumference of the projection of said cylindrical ceramic bore on the transverse plane P1. In this configuration, the metal rod may be self-centering in the cylindrical ceramic bore such that when mechanically coupled, the ceramic element and the metal rod are aligned on the same longitudinal axis X1. The three or more recesses may lie in the same transverse plane perpendicular to the longitudinal axis X1, or may be offset in the direction of the longitudinal axis.
In an advantageous embodiment of the method according to the invention,
the at least one protruding member comprises a substantially spherical ball having a ball diameter D, and
the insertion portion of the outer tube comprises at least one circular through hole having a diameter greater than the diameter D of the ball.
In this embodiment, the inner mandrel may comprise
A cylindrical proximal end portion (5p), the cylindrical proximal end portion (5p) having a radius R5 and comprising the stabilizing portion,
a cylindrical distal end portion having a radius R5d < R5, an
A frustoconical intermediate portion sandwiched between the cylindrical proximal and distal end portions, and
wherein the sphere diameter D is such that R8b < (D + R5D) < (R8+ δ) ═ R2, where δ is the tolerance δ between the outer tube and the cylindrical ceramic wall (R2-R8).
In this embodiment, the stabilizing portion of the inner mandrel may comprise at least one longitudinal strip that is elastically deformable and coupled to the inner mandrel at a first end and/or a second end of the at least one longitudinal strip. The central portion of the at least one longitudinal strip preferably defines a radius R5s, wherein at rest R5s ≧ R5, such that D ≧ (R24-R5s), wherein R24 is the distance between the longitudinal axis X1 and the bottom of the at least one depression, and wherein the longitudinal strip can flex when exposed to bending stresses, thereby reducing the radius R5s < R5, preferably at least to the value R5s ≦ (R24-D).
In an alternative embodiment, the at least one projecting member consists of a projection extending radially over a height Dp from a tip to a base rigidly coupled to a resiliently flexible longitudinal strip forming part of the outer tubular wall of the insertion portion of the outer tube. (Dp + R8) is preferably comprised between 90% and 105% of R24, wherein R24 is the distance between the longitudinal axis X1 and the closed end of the at least one recess.
In a further alternative embodiment, the kit according to the invention is such that
It further comprises a middle tube comprising a proximal end portion, a distal end portion, a middle tube wall and a middle tube aperture, wherein the distal end portion of the middle tube is insertable into the outer tube aperture from the proximal end of the outer tube,
the at least one projecting member consists of a projection extending radially over a height Dp from a tip to a base rigidly coupled to a resiliently flexible longitudinal strip forming part of the intermediate tube wall in the distal end of the intermediate tube, and wherein (Dp + R8b) is preferably comprised between 90% and 105% of R24, wherein R24 is the distance between the longitudinal axis X1 and the closed end of the at least one recess.
The insertion portion of the outer tube comprises at least one circular through hole having a diameter allowing the at least one projection to pass therethrough and engage therein, and
once the insertion portion of the outer tube is inserted into the ceramic bore and the intermediate tube is engaged in the outer tube bore so that the at least one protrusion is engaged in the at least one circular through hole and in the at least one recess, the inner mandrel has a diameter R5 so that it can be inserted into the intermediate tube bore from the proximal end of said intermediate tube to stabilize the at least one protrusion in the at least one recess.
The cylindrical ceramic bore may be a blind bore in the ceramic element or alternatively may form a through channel open at both ends.
The ceramic element preferably comprises fused silica.
In an advantageous embodiment, the ceramic element is a conveyor roller of a conveyor system for conveying products exposed to or at an elevated temperature of at least 200 ℃, preferably at least 500 ℃, more preferably at least 800 ℃, and wherein said insert of the outer tube is exposed to a temperature of at least 150 ℃, preferably at least 200 ℃, more preferably at least 300 ℃ and preferably not more than 500 ℃, more preferably not more than 400 ℃.
The invention also relates to a conveyor belt roller assembly for a conveyor belt system for conveying products exposed to or at an elevated temperature of at least 200 ℃, the conveyor belt roller comprising:
(a) a cylindrical body made of ceramic and extending along a longitudinal axis X1, comprising a first and a second end, each of the first and second ends being provided with a cylindrical ceramic bore defined by a cylindrical bore wall and extending along the longitudinal axis X1, wherein the cylindrical bore wall comprises at least one recess,
(b) first and second rods extending along the longitudinal axis and resiliently coupled to each of the first and second cylindrical ceramic bores, each of the first and second rods comprising:
(c) an outer tube including an insertion portion inserted into the corresponding cylindrical ceramic hole, the insertion portion being adjacent to a protrusion portion protruding from the corresponding cylindrical ceramic hole, and the outer tube further including:
an outer tube wall made of metal and defining an outer surface of the rod, wherein a portion of the outer tube wall of the insert is cylindrical with a radius R8 fitting the cylindrical ceramic hole,
an outer tube bore comprising a cylindrical portion of radius R8b, said outer tube bore extending from the proximal end along the longitudinal axis X1 and extending over the entire length of the protruding portion and further extending over at least a part of the length of the insertion portion,
(b) at least one protruding member comprising a protruding portion engaged in at least one recess of the ceramic element,
(c) an inner mandrel inserted into the outer tube bore from the proximal end of the outer tube such that the protruding portion of the at least one protruding member is elastically stabilized in the at least one recess by the stabilizing portion of the inner mandrel, and the rod is thus mechanically coupled to the ceramic element, characterized in that the outer tube cannot translate along the longitudinal axis X1 with respect to the ceramic bore,
wherein the stabilizing portions of the inner mandrel are radially resilient such that the at least one protruding member is removable from the at least one recess upon application of a force to the outer tube that is greater than a predetermined threshold force required to separate the metal rod from the ceramic element.
Drawings
These and other aspects of the invention will be explained in more detail, by way of example, and with reference to the accompanying drawings, in which:
figure 1 schematically shows a ceramic element and a metal rod of a kit according to the invention before mechanical coupling;
FIG. 2 shows the ceramic elements and metal rods of the kit of FIG. 1;
FIG. 3 shows a cross-sectional view comprising protruding members embedded in recesses of a ceramic element, wherein (a) the protruding members are separate elements of a kit according to the invention, and (b) and (c) the protruding members are integral parts of components of the kit according to the invention;
figures 4A to 6 show an embodiment of the kit described in example 1, wherein figure 4A shows a side view of the kit and a cross-sectional view along the line a-a in the side view;
FIG. 7 shows an embodiment of the kit described in example 2;
FIG. 8 shows an embodiment of the kit described in example 3;
FIG. 9 shows an embodiment of the kit described in example 4;
the drawings are not drawn to scale.
Detailed Description
The present invention relates to a kit for mechanically coupling a ceramic element 1 to a rod comprising an outer surface made of metal. The ceramic element may generally be a component of an arrangement used in high temperature applications. For example, the ceramic element may be a flow dam for controlling the flow of metal melt from the tundish into the mold; the flow plug is partially immersed in a metal melt at a temperature above 1400 ℃. Alternatively, the ceramic elements may be driven conveyor rollers of a conveying apparatus for conveying a load, such as glass or metal sheet, through a furnace for heat treating the sheet. The ceramic element may be made of any known ceramic material suitable for the application for which it is designed. Specifically, the ceramic element may be made of fused quartz, graphite, alumina, an electrofused material, or the like. In addition to high temperature conveyor belt rollers, ceramic elements may be used in a variety of applications, including structural components suspended in high temperature applications, such as flow restrictors for tundishes in metallurgical equipment; glass bending fittings, stirrers in high temperature liquids (such as metal or glass melts, etc.) and skimmers.
As illustrated in fig. 1, the ceramic element 1 comprises at least one ceramic bore 2, which ceramic bore 2 comprises a cylindrical portion. For the sake of clarity and simplicity, the expression "cylindrical ceramic hole" will be explained hereinafter as "ceramic hole made up of cylindrical parts". The cylindrical ceramic holes may be blind or through holes, forming open through channels at both ends. The cylindrical ceramic bore extends along a longitudinal axis X1 and is defined by a cylindrical bore wall. In the cylindrical ceramic cell wall, at least one recess 4 is included. Such a recess is advantageously a closed-end cavity, like for example a hollow, a notch or a groove in a wall of a ceramic cell. However, in some embodiments, the recess may be a through-hole extending generally radially with respect to the longitudinal axis X1.
As shown in fig. 1 and 2, a metal rod may be inserted into the cylindrical ceramic bore to mechanically couple it to the ceramic element. The rod comprises an outer tube 8 having an outer tube wall made of metal. The outer tube comprises an insert 8i comprising a cylindrical portion 8c adapted to be inserted into a cylindrical ceramic bore, and a protrusion 8p, the protrusion 8p being adapted to be coupled to an external component, such as a translational and/or rotational drive system.
The insertion portion 8i is a portion of the outer tube that is inserted into the cylindrical ceramic hole 2 when the ceramic element is coupled to the metal rod. The insert comprises a cylindrical portion 8c with a radius R8, which cylindrical portion 8c cooperates with a cylindrical ceramic bore with a radius R2. The insert can thus be inserted into the cylindrical ceramic bore, and the outer tube 8 can be mechanically coupled to the ceramic element 1 by means of a mechanism explained in detail below, so that the outer tube cannot freely translate along the longitudinal axis X1 with respect to the ceramic element. In order to obtain a satisfactory mechanical coupling, the rod should not be allowed to reciprocate within the cylindrical ceramic bore at the operating temperature. By ensuring that the radius R8 of the outer tube is within the tolerance δ, substantially equal to the radius R2 of the cylindrical ceramic bore 2 at the expected operating temperature (and δ below the radius R2), reciprocation of the rod is prevented.
Considering the different CTEs of ceramic material and metal, for high temperature applications of the cartridge according to the invention, the radius R8 of the cylindrical portion 8c at room temperature (═ 20 ℃) is generally smaller than the radius R2 of the cylindrical ceramic bore 2 by an upper value (δ + (Δ R8- Δ R2)) (cf. the following derivation:
wherein Δ Ri ═ α Ri (rt) Δ T (i ═ 2 or 8); ST-room temperature, RT-CTE) so that the insert 8i can be inserted loosely into the cylindrical ceramic bore at room temperature, but fits snugly within the tolerance δ at elevated operating temperatures.
The protruding portion 8p of the outer tube 8 is a portion of the outer tube that protrudes from the ceramic element 1 when the insertion portion 8i is inserted into the ceramic cylindrical hole 2. The projection 8p may be cylindrical, but may have any shape suitable for interacting with other components of the assembly, such as a drive mechanism coupled with a rod, for example a polygonal cross-section as represented in fig. 1 and 2.
The outer tube 8 is hollow and comprises an outer tube bore comprising a cylindrical portion of radius R8b (smaller than the radius R8 of the insert 8i) and extending over the entire length of the projection 8p and over at least a portion of the length of the insert 8 i. The outer tube bore is essential to the invention as it serves to accommodate other components of the stem used to mechanically couple it to the ceramic element.
When assembling the kit according to the invention, the outer tube 8 of the rod is inserted into the cylindrical ceramic bore, as illustrated in figure 2. However, it must be mechanically coupled to the ceramic element such that it cannot freely translate along the longitudinal axis X1 but may rotate about the longitudinal axis X1 with respect to the ceramic element. In order to mechanically couple the outer tube to the ceramic element, the kit according to the invention further comprises at least one protruding member 7, which protruding member 7 comprises a protruding portion that is insertable into the at least one recess 4 of the ceramic element. As illustrated in fig. 3(a), the protruding member may be a separate component 7b of the kit, or it may be an integral part 7p of a component of the kit, such as the outer tube 8 or the intermediate tube 58 (see fig. 3(b), 6 and 7) described below. In any case, once the kit according to the invention is assembled, the at least one protruding member 7b, 7p is engaged into the at least one corresponding recess of the cylindrical ceramic hole by various mechanisms described below, and the metal rod is mechanically coupled to the outer tube 8.
Since the at least one protruding member is inserted into the corresponding recess, it may also be possible to withdraw it from the recess in the absence of the fixation means, and the outer tube will then no longer be mechanically coupled to the ceramic element. It is therefore necessary to lock at least one projecting member in a corresponding recess. This is achieved by inserting the inner mandrel 5 into the outer tube bore. The inner mandrel includes a cylindrical portion having a radius R5, the radius R5 being less than or substantially equal to the radius R8b of the outer tube bore (R5 ≦ R8 b). The whole or a part of the inner mandrel may be made of metal or other material (such as, for example, an elastomeric material) depending on the intended operating temperature to which the rod will be exposed in use. The rigid or (according to a preferred embodiment of the invention) elastic locking of the protruding members in the corresponding recesses may be achieved by selecting the geometry and/or material of the inner mandrel.
In one embodiment, the insertion portion 8i of the outer tube comprises a through hole 9 allowing each of the at least one or more protruding members 7b, 7p to move radially outwards to engage into the corresponding one or more recesses 4 of the cylindrical ceramic bore 2 and thereby mechanically couple the outer tube to the ceramic element. The protruding members 7b, 7p are preferably made of metal, but they may be made of a ceramic material, or depending on the intended operating temperature, a polymer material, and even an elastic material such as an elastomer.
In this embodiment, the protruding member 7b may be a separate component of the kit. For example, as represented in fig. 3(a), 5 and 6, the protruding member 7b may be in the shape of a sphere of diameter D, which may be inserted into the outer tube hole when the outer tube is inserted into the cylindrical ceramic hole, and once the through hole 9 faces the corresponding recess 4, the sphere may be radially pushed out through the corresponding through hole 9 and into the recess, while still spanning the through hole 9 and resting on the outer surface of the mandrel, in particular on the stabilizing portion 5s of the mandrel.
Alternatively, as illustrated in fig. 7, the protruding member may be formed by a protrusion 7p extending radially in height Dp from the tip to a base rigidly coupled to a resiliently flexible longitudinal strip forming part of the intermediate tube 58. The height Dp is such that (Dp + R8) is preferably comprised between 90% and 105% of R24, wherein R24 is the distance between the longitudinal axis X1 and the closed end of the at least one recess 4. Each protruding member 7p comprises a protruding portion preferably having the geometry of a spherical cap with a diameter D.
The size of the through hole 9 on the outer tube wall must be large enough to allow the protruding part of the protruding member 7b, 7p to be inserted into the recess 4 through the through hole 9, and small enough that the protruding member, once engaged in the corresponding recess, contacts the through hole wall substantially within the entire circumference of the through hole. In this way, the outer tube is mechanically coupled to the ceramic element in the longitudinal direction X1 without reciprocating. Thus, the protruding portion of the at least one protruding member 7b, 7p, the at least one recess 4 and the at least one through hole 9 advantageously have substantially the same spatial extent along the longitudinal axis X1. In this way, relative axial movement along the longitudinal axis X1 does not occur between the ceramic element 1, the projecting member 7 and the outer tube 8.
In an alternative embodiment illustrated in fig. 3(b) and 8, the outer tube does not include any through holes. Instead, the projecting member 7p is an integral part of the outer tube. Advantageously, the protruding portion of the protruding member protrudes from the outer tube wall such that it can be inserted into the recess 4 when the cylindrical portion 8c of the outer tube 8 is inserted into the ceramic bore 2. Also in this case, the protruding portion of the at least one protruding member 7p and the at least one recess 4 advantageously have substantially the same spatial extent along the longitudinal axis X1, for the reasons disclosed in the previous section. The height of the protruding member is smaller than the embodiment illustrated in fig. 7 and is substantially equal to the depth of the recess 4 (R24-R2).
During assembly of the kit according to the invention, the inner mandrel 5 is thus inserted either directly into the outer tube bore or, if an intermediate tube has been inserted in the outer tube bore, from the proximal end of the outer tube 8 or the intermediate tube 58. The inner spindle serves for stabilizing the protruding part of the at least one protruding member 7b, 7p in the at least one recess 4 by means of the stabilizing portion 5s of said inner spindle. The stabilizing portion 5s of the mandrel 5 therefore requires the following geometry and dimensions: so that, once inserted into the cylindrical portion 8c of the outer tubular bore or of the intermediate tube 58, the projecting members 7b, 7p are sandwiched between said stabilizers and the walls of the recess 4.
When the protruding member 7b is a separate component of the kit and when the outer tube 8 comprises a through hole 9 to accommodate such protruding member 7b, the protruding member 7b may have the following shape and dimensions: so that it protrudes into the outer tube bore when it is secured in the recess 4. In this case, the radius R5s of the stabilizing portion 5s of the mandrel is therefore significantly smaller than the outer tube bore radius, but large enough to stabilize the protruding member radially snugly in the through hole 9 and recess 4 at the intended operating temperature.
When the protruding member 7p is an integral part of the outer tube 8 or the intermediate tube 58 (see fig. 7 and 8) and protrudes from the outer tube wall or the intermediate tube wall, the stabilisation of the inner mandrel 5 is advantageously cylindrical and has a radius R5. If the protruding member 7p is an integral part of the outer tube 8, then R5 may be substantially equal to the radius R8b of the cylindrical portion 8c of the outer tube bore at the desired operating temperature. Similarly, if the protruding member 7p is an integral part of the intermediate tube 58, R5 may be substantially equal to the radius R58b of the intermediate tube bore at the expected operating temperature. In the case of elastic locking of the protruding member in the corresponding recess, the stabilizer 5s has an elastic structure and/or comprises an elastic material and may have a radius R5s > R5, such that when the protruding member is engaged in the recess and contacts its rear wall, the 5s is in a radially compressed state and is radially pressed down until the radius R5 at the predetermined operating temperature is reached.
When the inner mandrel 5 is inserted into the outer tube bore or intermediate tube bore, the protruding portion of the at least one protruding member 7b, 7p is stabilized in the at least one recess 4 by the stabilizing portion of the inner mandrel 5 and the metal rod is thus mechanically coupled to the ceramic element 1, characterized in that the outer tube cannot translate along the longitudinal axis X1 with respect to the ceramic bore 2. It is important to note that the mechanical coupling in terms of translation is achieved in both directions along the longitudinal axis X1 when the protruding portion of the at least one protruding member 7b, 7p is inserted into the at least one recess 4. Therefore, the metal rod cannot be translated into or slid into or out of the ceramic bore 2 along the longitudinal axis X1.
The coupling is preferably elastic and the stabilizing portion 5s of the spindle may have an elastic structure and/or comprise an elastic material. Elasticity is the ability of a (viscoelastic) elastic material to absorb energy when deformed and release at least a portion of that energy when removed. Elasticity is observed in elastomeric materials when the applied stress is below the yield stress (above which the material will plastically deform) or below the fracture stress (above which the material will fracture). The behavior of viscoelastic materials depends on temperature and strain rate. If the viscoelastic material deforms at a higher rate and/or lower temperature, it behaves more like an elastic material as discussed above. A viscoelastic material behaves more like a viscous material if it deforms at a lower rate and/or at a lower temperature. The higher the viscous component of the deformation, the lower the rate at which the material can release the energy absorbed during deformation and return to its original configuration.
Next, the terms "force", "stress" and "torque" may be used depending on the context. All of these terms relate to "force". Torque τ is a rotational force and its magnitude is the product of a force vector F and a distance vector r separating the point of application and the point or axis of rotation (τ Nm ═ fx r). The stress δ is calculated as the force F divided by the area a on which the force is applied (δ [ Pa ] ═ F/a). Whenever the terms "torque" or "stress" are used, they may be easily re-referenced to "force", and the use of these terms is limited to specific embodiments where the use of these terms is considered more accurate than the use of the term "force".
When a stress is applied to the outer tube 8, the stress is transferred to the ceramic element by at least one protruding member engaging in at least one recess of the ceramic element bore. The protruding member is extruded out of the recess by transmitting stress applied to the outer tube 8 to the protruding member, but is held by the stabilizing portion 5s of the inner mandrel 5. The threshold force or stress at which the outer tube 8 separates from the ceramic element may be predefined by: the stabilisation part 5s of the inner mandrel is designed to deform sufficiently upon application of a stress equal to the desired threshold stress, to dislodge the at least one protruding member from the at least one recess and thus separate the outer tube 8 from the ceramic element. Preferably, the threshold stress is selected to be below the fracture resistance of the ceramic element (above which the ceramic element will fracture). In this way, if a stress higher than the fracture resistance of the ceramic element is applied to the outer tube, the latter is detached from the ceramic element by the deformation of the stabilizer, thereby moving out the at least one protruding member, thus preventing the ceramic element from fracturing. The stabilizers 5s are considered to be elastic. In contrast, if the threshold value is higher than the fracture resistance of the ceramic element, the stabilizer 5s is considered to be rigid because the outer tube does not separate from the ceramic element and the fracture resistance of the ceramic material will be destroyed. In the present invention, it is preferable that the stabilizer is elastic.
In a preferred embodiment, the threshold stress is lower than the yield stress or the fracture stress of the elastic stabilizer 5 s. In this way, when the stress applied to the outer tube 8 falls below the threshold stress, the elastic stabilizers return to or near their original shape, thus engaging the at least one protruding member into the at least one recess. This is very advantageous in applications where the outer tube transmits torque to the ceramic element. If the peak value of the torque is higher than the threshold stress, the outer tube is separated from the ceramic element, thus preventing the ceramic element from being broken. As soon as the torque drops below the threshold stress, the outer tube is automatically coupled again to the ceramic element and can again transmit the torque to the ceramic element. This is particularly advantageous in applications where the ceramic element is a cylindrical transfer element.
If the threshold stress is higher than the yield stress or fracture stress of the stabilizer 5s, the ceramic element is protected from fracture in the case where the peak value of the stress is higher than the fracture resistance strength of the ceramic element, but the coupling between the outer tube and the ceramic element cannot be restored once the stress falls below the threshold stress since the stabilizer 5s is permanently deformed or fractured. In this case, the inner mandrel acts like a sacrificial fuse instead of the ceramic element breaking. The new inner mandrel must replace the permanently deformed or broken inner mandrel to restore the coupling of the outer tube to the ceramic element.
In one example of the invention, the cylindrical bore wall 2 of the ceramic element 1 may comprise an annular recess, forming a circumferential groove in said cylindrical bore wall. In this configuration, a mechanical coupling in translation between the ceramic element 1 and the metal rod is obtained along the longitudinal axis X1. However, with the annular recess 4, and ignoring any friction, the metal rod is free to rotate about its longitudinal axis X1. A mechanical coupling in terms of translation is thus obtained between the metal rod and the ceramic element, but no significant torque can be transmitted from the metal rod to the ceramic element.
If a mechanical coupling in terms of rotation is desired in addition to a mechanical coupling in terms of translation, the cylindrical bore wall of the ceramic element 1 may also comprise at least one recess 4, which recess 4 has a limited size in the circumferential direction with respect to the longitudinal axis X1, and the protruding portion of the protruding member 7b, 7p inserted in such a recess 4 has substantially the same size in the circumferential direction with respect to the longitudinal axis X1 as the recess. In the case illustrated in fig. 3(a), 5,6 and 8, in which the protruding members 7b, 7p are engaged in the recesses by the through holes 9, the through holes 9 then advantageously have a dimension in the circumferential direction with respect to the longitudinal axis X1 that allows the protruding members to contact the through hole wall over substantially the entire circumference of the through holes. In this configuration, once the protruding portion is stabilized into the recess by the stabilizing portion 5s by means of the mandrel 5, the metal rod is mechanically coupled to the ceramic element 1 both in translation and in rotation, characterized in that the outer tube 8 cannot slide with respect to the ceramic element along the longitudinal axis X1 nor rotate about the longitudinal axis X1. Thus torque can be transferred from the metal rod to the ceramic element by rotating the outer tube.
In the example of the invention, the cylindrical ceramic bore wall comprises three or more recesses 4 and the projections of the three or more recesses on a transverse plane P1 perpendicular to the longitudinal axis X1 are evenly distributed on the circumference of the projection of said cylindrical ceramic bore on the transverse plane P1. This configuration is particularly interesting because by having at least three recesses 4 evenly distributed around the longitudinal axis X1, the metal rod can be self-centered in the cylindrical ceramic hole so that the ceramic element 1 and the metal rod are aligned on the same longitudinal axis X1 when mechanically coupled. This is particularly important for the metal rod to be mechanically coupled in rotation to the ceramic element, wherein the longitudinal axis X1 of the metal rod must be coaxial with the desired axis of rotation of the ceramic element.
Three or more recesses 4 may belong to the same transverse plane of the cylindrical bore wall 2 perpendicular to the longitudinal axis X1. In another configuration, three or more recesses may be distributed axially offset with respect to the longitudinal axis X1. This may be advantageous for thin ceramic structures, since three or more recesses aligned on the same circumference of the cylindrical ceramic hole may impair the mechanical properties of the ceramic element.
In an embodiment departing from the invention, the stabilizing portion 5s of the inner mandrel 5 may be radially rigid. The rigid stabilizers are characterized herein as having a compressive or flexural modulus of at least 0.1GPa at the intended operating temperature. In such an example of the invention, the protruding portion of the at least one protruding member is rigidly stabilized in the at least one recess. Thus, when a translational or rotational stress is applied between the outer tube 8 and the ceramic element 1, it is not possible to remove the protruding portions of the protruding elements 7b, 7p from the recess 4 without breaking the mechanical coupling.
In an alternative embodiment of the invention, the stabilizing portion 5s of the inner mandrel 5 has a radial elasticity such that the protruding portion of the protruding member 7b, 7p can be pressed down onto the elastic portion and thus be moved out of the recess 4 when a force greater than a predetermined threshold force is exerted on the outer tube 8. This is particularly advantageous for applications where torque can be transmitted between the metal rod and the ceramic element 1 and where this transmitted torque cannot exceed a given threshold value in order to avoid fracture of the ceramic element. For example, the ceramic elements 1 may be a series of conveyor rollers of a conveyor system, the rotation of which is driven by an electric motor to allow the load to be conveyed. In the event that the weight of the load exceeds the allowable load, or if the load is blocked and cannot move under the action of the rollers rotating, the blockage may cause unnecessary friction between the load and the conveyor belt, possibly damaging some of the rollers. When the magnitude of the torque reaches a given threshold, removal of the protruding portion of the protruding member from the recess by means of the protruding member pressing radially down on the radially resilient stabilisation part of the mandrel allows the metal rod to rotate relative to the ceramic element without damaging any of the components. When the blockage is removed, the protruding member eventually faces the recess again, and can engage with the recess to re-establish the rotational mechanical coupling. The predetermined threshold of torque triggering the separation of the metal rod from the ceramic element can be fine tuned by varying the level of elasticity (stiffness) of the stabilizers of the mandrel.
In an example of the invention, the inner mandrel 5 may comprise radially elastic stabilizers having a geometry defining an elastically deformable structure. As illustrated in fig. 4A to 6, such a geometry may be defined, for example, by at least one longitudinal strip 6i, which longitudinal strip 6i is elastically deformable and coupled to the inner mandrel at least at a first and a second end of the longitudinal strip. In such a configuration, the value of the threshold force or torque may be fine tuned by selecting a material with appropriate flexural stiffness and/or by varying the thickness of the band. The flexural modulus of the tape may be of the order of no more than 0.1GPa, preferably no more than 0.01 GPa. As shown in fig. 4A to 6, a hollow is provided below the longitudinal band and possibly on the side of the longitudinal band to provide room for elastic deformation of the longitudinal band when the torque reaches a threshold value.
In an alternative embodiment, the stabilizing portion 5s of the mandrel 5 may be in the form of a hollow tube having an elastically deformable mandrel wall dimension to dislodge the protruding member from the corresponding recess upon application of a force higher than a threshold force.
In other examples of the invention, the inner mandrel 5 may be a complete cylinder at the intended operating temperature, comprising a stabilisation made of an elastic material (e.g. an elastomeric material). By elastic material is meant a material having a compressive modulus of not more than 0.1GPa, preferably not more than 0.01 GPa. In such a configuration, the value of the threshold force or torque can be fine-tuned by selecting a material with suitable elasticity, which can surround a cylindrical inner core made of a rigid material, and/or the thickness of said material.
Examples
Example 1
In fig. 4A to 6, an embodiment of a kit for mechanically coupling a ceramic element 1 to a metal rod according to the invention is shown. In this kit, the cylindrical hole wall comprises three recesses 4 lying in the same transverse plane perpendicular to the longitudinal axis X1, evenly distributed over the circumference of said cylindrical ceramic hole. The protruding member 7b comprises three substantially spherical spheres with a sphere diameter D, which spheres can be engaged into the recesses 4 of the ceramic element through three corresponding through holes 9 provided in the cylindrical portion 8c of the outer tube wall. The three through holes 9 have a diameter larger than the sphere diameter D. These three balls can thus be jammed inside the outer tube bore when the outer tube is inserted into the cylindrical ceramic bore, and can engage into the corresponding recess through the through hole when the through hole faces the corresponding recess. In the present example in which the projecting member is a sphere 7b, the recess 4 is advantageously substantially spherical and has a radius of curvature which is smaller than or preferably substantially equal to the radius D/2 of the spherical sphere 7 b. In a preferred embodiment, the recess and the substantially spherical ball have the same radius of curvature.
As shown in fig. 5 and 6, the inner mandrel 5 has a particular geometry comprising three distinct portions:
a cylindrical proximal portion 5p, the cylindrical proximal portion 5p having a radius R5 and comprising the stabilizing portion,
a cylindrical distal end portion 10, the cylindrical distal end portion 10 having a radius R5d < R5, and
a frustoconical intermediate portion 11, this frustoconical intermediate portion 11 being sandwiched between cylindrical proximal and distal end portions.
The sphere diameter D is such that R8b ≦ (D + R5D ≦ (R8+ δ) ═ R2, where R8b is the outer tube bore radius, R8 is the outer radius of the insertion portion 8i of the outer tube, R2 is the radius of the cylindrical ceramic bore, and δ is the tolerance between the outer tube and the cylindrical ceramic wall δ ═ R2-R8. The ball is preferably made of metal, but it may be made of a ceramic material, or depending on the intended operating temperature, a polymer material, and even an elastic material such as an elastomer.
In this embodiment of the invention, the coupling of the metal rod to the ceramic element 1 is performed as follows. The inner mandrel 5 is first introduced into the outer tube bore up to the depth of the cylindrical distal end portion 10 with radius R5d facing the through hole 9 of the outer tube 8. The ball 7b can be introduced through the through hole 9 to rest on the cylindrical distal end 10. The balls must not protrude from the outer tube wall through the corresponding through holes 9 beyond the tolerance δ (R2-R8) so that the assembly consisting of the outer tube, the inner mandrel and the balls can be inserted into the cylindrical ceramic bore. Therefore, the diameter D of the sphere is less than or equal to (R2-R5D). On the other hand, when the inner mandrel is in the outer tubular bore, the ball should not roll freely away from the distal end 10 of the inner mandrel. Therefore, the diameter D of the sphere is not less than (R8 b-R5D). Thus, a sphere having a diameter D defined as (R8 b-R5D). ltoreq.D.ltoreq.R 2-R5D is axially blocked in a position resting on the distal end 10 of the inner mandrel and embedded in the corresponding through hole 9. The spheres can be fixed radially in this position in the insertion through holes 9 for a short time, within the time required for inserting the outer tube into the cylindrical ceramic bore 2, by using magnets, by coating the spheres with grease adhering to the contact surfaces, or by using an adhesive tape wound around the outer tube at the level of the through holes.
The inserted portion of the outer tube 8 can be inserted into the cylindrical ceramic bore until the through-holes face the corresponding recesses 4, at which point the inner mandrel engages in the outer tube bore and the ball 7b rests on the distal end 10 of the inner mandrel and is embedded in each corresponding through-hole 9. A flange 14 is advantageously provided between the insertion portion 8i and the extension portion 8p of the outer tube. Such a flange thus abuts against the ceramic element when the through hole in the outer tube faces the recess in the ceramic bore. The angular orientation of the outer tube relative to the location of the recess may be indicated by appropriate markings on the outer tube (e.g., on the flange) and on the ceramic element.
In this stage, the inner mandrel can be pushed deeper into the outer tube bore. Due to the diameter D of the ball (as discussed above), the ball cannot be removed from the through hole when the inner mandrel is pushed forward. The ball thus rolls along the surface of the distal part of the inner mandrel until it reaches the frustoconical intermediate part 11, where it moves radially outwards as it rolls upwards on the slope formed by said frustoconical intermediate part 11 until it reaches the cylindrical proximal part 5p of the inner mandrel and stops at the stable part 5 s. As discussed above, the stabilizer 5s has a radius R5s ≧ R5, where R5 is the radius of the cylindrical proximal end of the inner mandrel. If the stabilisation of the inner spindle is rigid, R5s ═ R5, or only slightly above the tolerance range δ measured at the expected operating temperature. If the stabilizers are elastic, R5s may be larger than R5, as long as the stabilizers are deformable with the ball pressing the elastic portion until R5s — R5.
If the stabilizer 5s is elastic, it may comprise an elastic material having a desired compressibility at the intended operating temperature. As discussed above, its radius R5s may be equal to the radius R5 of the cylindrical proximal end of the inner mandrel, or the radius R5s may be greater than R5. In this case, the elastic stabilisation part may form a projection and may define a cradle for receiving the ball. Upon application of a stress above the predetermined threshold, the elastic stabilizer may be further deformed until it defines a radius less than or equal to R2-D, such that the outer tube may translate along the longitudinal axis X1 and rotate about the longitudinal axis X1.
Alternatively, the elasticity of the stabilizer may be structurally realized. For example, as illustrated in fig. 4A to 6, the mandrel 5 is a hollow cylinder, and the stabilizing portion 5s of the mandrel comprises an elastically deformable longitudinal strip 6 i. The longitudinal strip is coupled to the inner mandrel at first and second ends thereof. The central portion of at least one longitudinal band preferably defines a radius R5s, wherein R5s ≧ R5 at rest. If the radius R5s is greater than the radius R5 of the cylindrical proximal end of the inner mandrel, the longitudinal band, at rest, forms an arch defining said radius R5s, which can be deformed by a sphere until the radius defined by the longitudinal band is equal to R5. Upon application of a stress above the predefined threshold, the longitudinal bands may be further deformed until they define a radius less than or equal to R2-D such that the outer tube may translate along the longitudinal axis X1 and rotate about the longitudinal axis X1.
Example 2
In an alternative embodiment illustrated in fig. 7, the kit further comprises an intermediate tube 58 defined by an intermediate tube wall and having a distal end portion 58d, the intermediate tube 58 being insertable into the outer tube bore from the proximal end of the outer tube 8. The intermediate tube comprises a protrusion 7p extending radially in height Dp from the tip to a base rigidly coupled to a resiliently flexible longitudinal strip 58s forming part of the intermediate tube wall and coupled in a cantilever structure to a proximal end 58p of the intermediate tube. The radial height Dp of the protrusion is preferably defined as (Dp + R8b) comprised between 90% and 105% of R24, wherein R8b is the outer tube hole radius and R24 is the distance between the longitudinal axis X1 and the bottom of the recess 4. The outer tube 8 is the same as that described in example 1. The insertion portion 8i of the outer tube 8 thus comprises a circular through hole 9, the diameter of which allows the projection 7p to pass therethrough and engage.
In this embodiment of the invention, the coupling of the metal rod to the ceramic element 1 is performed as follows. The insertion portion 8i of the outer tube is first inserted into the ceramic bore 2 until the through-hole faces the recess 4 of the ceramic bore. Also, a flange 14 is advantageously provided between the insertion portion 8i and the protruding portion 8p of the outer tube. Such a flange thus abuts against the ceramic element when the through hole in the outer tube faces the recess in the ceramic bore. The angular orientation of the outer tube relative to the location of the recess may be indicated by appropriate markings on the outer tube (e.g., on the flange) and on the ceramic element.
Then, as illustrated in fig. 7(b), the distal end portion 58d of the intermediate tube 58 is engaged in the outer tube bore, with the longitudinal strip 58s including the projections 7p bent inwardly so that the projections abut within the outer tube bore until they reach the level of the through-bore. In this stage, the flexural stress on the longitudinal strip is relieved, as the protrusion can move radially upward through the through hole and engage into the recess, as illustrated in fig. 7 (c). Once the projections 7p are engaged in the circular through holes and in the recesses 4, the inner mandrel 5, having a radius R5 substantially equal to the intermediate tube bore radius R58b, may be inserted from the proximal end 58p of the intermediate tube 58 into the intermediate tube bore 58 b. The projection 7p is thus stabilized in the recess 4.
Also, if the stabilizing section of the inner mandrel is rigid, a rigid mechanical coupling is formed between the outer tube and the ceramic element. If the stabilisation portion of the inner mandrel is elastically flexible, the protrusion may be withdrawn from the recess by bending the longitudinal strip when a stress above a threshold is applied. The threshold may be controlled by selecting the compressibility of the inner mandrel. As discussed with respect to example 1, the elasticity of the stabilizers may be achieved by selection of elastic materials and/or by design of the elastic structure.
Example 3
As shown in fig. 8, in an alternative embodiment of the kit according to the invention, the outer tube 8 does not comprise any through holes, but comprises a protrusion 7p extending radially in height Dp from the tip to the base, which is rigidly coupled to a resiliently flexible longitudinal strip 8s forming part of the outer tube wall of the insertion portion 8i of the outer tube and coupled to the proximal end portion 8p of the outer tube in a cantilever structure. The radial height Dp of the protrusion is preferably defined as (Dp + R8) comprised between 90% and 105% of R24, where R8 is the outer tube wall radius and R24 is the distance between the longitudinal axis X1 and the bottom of the recess 4.
In this embodiment of the invention, the coupling of the metal rod to the ceramic element 1 is performed as follows. As illustrated in fig. 8(b), the insertion portion 8i of the outer tube is first inserted in the ceramic bore 2, at which point the longitudinal strip comprising the projections 7p is bent inwards so that the projections cling within the cylindrical ceramic bore 2 until they reach the level of the recess 4. In this stage, the flexural stress on the longitudinal strip is relieved, as the protrusion can move radially upward as it engages into the recess, as illustrated in fig. 8 (c). Also, a flange 14 is advantageously provided between the insertion portion 8i and the protruding portion 8p of the outer tube. Such a flange thus abuts against the ceramic element when the through hole in the outer tube faces the recess in the ceramic bore. The angular orientation of the outer tube relative to the location of the recess may be indicated by appropriate markings on the outer tube (e.g., on the flange) and on the ceramic element.
Once the projections 7p are engaged in the recesses 4, the inner mandrel 5, having a radius R5 substantially equal to the outer tube bore radius R8b, can be inserted into the outer tube bore 8b from the proximal end 8p of said outer tube 8. The projection 7p is thus stabilized in the recess 4. Also, if the stabilizing section of the inner mandrel is rigid, a rigid mechanical coupling is formed between the outer tube and the ceramic element. If the stabilisation portions of the inner mandrel are elastically flexible, the protrusions may be withdrawn from the recesses by bending the longitudinal strips when a stress above a threshold is applied. The threshold may be controlled by selecting the compressibility of the inner mandrel. As discussed with respect to example 1, the elasticity of the stabilizers may be achieved by selection of elastic materials and/or by design of the elastic structure.
Example 4:
in fig. 9, an embodiment of a kit for mechanically coupling a ceramic element 1 to a metal rod according to the invention is shown. In this kit, the cylindrical hole wall comprises three recesses 4 lying in the same transverse plane perpendicular to the longitudinal axis X1, evenly distributed over the circumference of said cylindrical ceramic hole. The outer tube 8 is the same as the outer tube described in examples 1 and 2, wherein the cylindrical portion 8c includes three through holes 9. The protruding member 7b comprises three substantially spherical spheres with a sphere diameter D which can be engaged into the recesses 4 of the ceramic element through three corresponding through holes 9 of the outer tube wall. The three through holes 9 have a diameter larger than the sphere diameter D. The three balls may thus be caught within the outer tube bore when the outer tube is inserted into the cylindrical ceramic bore, and may engage into the corresponding recess through the through-hole when the through-hole faces the corresponding recess. As with invention example 1 (where the protruding member is a sphere 7b), the recess 4 is advantageously substantially spherical and has a radius of curvature less than or preferably substantially equal to the radius D/2 of the spherical sphere 7 b. In a preferred embodiment, the recess and the substantially spherical ball have the same radius of curvature.
As shown in fig. 9(c), the inner mandrel 5 has a specific geometry comprising a stabilizer 5s having a cross section which is not a rotational geometry but preferably axisymmetric with respect to the longitudinal axis of the inner mandrel. For a system comprising N spheres 7b, the cross section of the stabilizer 5s comprises N locking surfaces 5L with a radial dimension R5L and N insertion surfaces 5i with a radial dimension R5i < R5L. In fig. 9, N is 3. These locking surfaces 5L and insertion surfaces 5i are evenly distributed in an alternating sequence over the circumference of said inner spindle 5.
The sphere diameter D is such that R8b < (D + R5i) < R2, where R8b is the radius of the outer tube bore and R2 is the radius of the cylindrical ceramic bore 2, as explained above. The ball is preferably made of metal, but it may be made of a ceramic material or, depending on the intended operating temperature, a polymer material.
In this embodiment of the invention, the coupling of the metal rod to the ceramic element 1 is performed as follows. The inner mandrel 5 is first introduced into the outer tube bore to a depth at which the stabilizers 5s of the mandrel face the through-holes 9 of the outer tube, and is introduced into the outer tube bore in an angular orientation such that the insertion surfaces 5i of the stabilizers 5d face the through-holes 9. The spheres 7b can then be introduced through the through holes 9 to rest on the corresponding three insertion surfaces 5 i. The balls must not protrude from the outer tube wall through the corresponding through holes 9 beyond the tolerance δ (R2-R8) so that the assembly consisting of the outer tube, the inner mandrel and the balls can be inserted into the cylindrical ceramic bore. Therefore, the diameter D of the sphere is less than or equal to (R2-R5 i). On the other hand, when the inner mandrel is located in the outer tube bore, the ball should not roll freely on the insertion surface of the inner mandrel. Therefore, the diameter D of the sphere is not less than (R8 b-R5 i). Thus, a sphere having a diameter D defined as (R8 b-R5 i). ltoreq.D.ltoreq.R 2-R5 i is blocked between the insertion surface and the through hole in which the sphere is inserted, and thus may not be removed from the insertion portion 5 s. The ball can be fixed radially in this position embedded in the through hole 9 during the time required for inserting the outer tube, the inner mandrel and the ball into the cylindrical ceramic hole, by using magnets, by coating the ball with grease adhering on the contact surface, or by using an adhesive tape wound around the outer tube at the level of the through hole.
The insertion portion of the outer tube 8 can be inserted into the cylindrical ceramic hole until the through hole faces the corresponding recess 4, with the inner mandrel engaged in the outer tube hole, the ball 7b resting on the insertion surface 5i of stable cross section and being inserted into each corresponding through hole 9. A flange 14 is advantageously provided between the insertion portion 8i and the extension portion 8p of the outer tube. Such a flange thus abuts against the ceramic element when the through hole in the outer tube faces the recess in the ceramic bore. The angular orientation of the outer tube relative to the location of the recess may be indicated by appropriate markings on the outer tube (e.g., on the flange) and on the ceramic element.
In this stage, the inner mandrel may be rotated about the longitudinal axis X1 relative to the outer tube bore. Due to the diameter D of the ball (as discussed above), the ball cannot move away from the through hole when the inner mandrel is rotated through an angle of 360 °/2N. In the case of 3 spheres in fig. 9, the inner spindle can be rotated through an angle of 60 °. The rotation of the inner spindle 5 serves to guide the ball from the insertion surface 5i onto the locking surface 5L of the stabilizing section 5s of the inner spindle. The cross section of the insertion portion must be such that the ball 7b can roll from the insertion surface to the locking surface as the inner spindle rotates. Thus, the transition between the insertion surface and the adjacent locking surface is preferably smooth and should not have a radial dimension greater than R5L so that a ball striking the bottom surface of the recess would block rotation of the inner spindle. During rotation of the inner spindle, the balls move radially outward and engage into the recesses as they roll from an insertion surface spaced a distance R5i from the longitudinal axis X1 to a locking surface spaced a distance R5L > R5i from the longitudinal axis X1. Since R2< (R5L + D) ≦ R24, when the balls rest on the corresponding locking surfaces, they engage in the recesses and are embedded in the through holes of the outer tube, thus mechanically coupling the outer tube to the ceramic element.
Also, if the stabilizing section of the inner mandrel is rigid, a rigid mechanical coupling is formed between the outer tube and the ceramic element. If the stabilisation portions of the inner mandrel are elastically flexible, the protrusions may be withdrawn from the recesses by bending of the longitudinal strips when a stress above a threshold is applied. The threshold may be controlled by selecting the compressibility of the inner mandrel. As discussed with respect to example 1, the elasticity of the stabilizers may be achieved by selection of elastic materials and/or by design of the elastic structure.
Concluding sentence
As described above, the present invention provides a reliable solution to mechanically couple metal rods to ceramic elements in a variety of configurations. In particular, it allows a mechanical coupling in terms of translation and/or rotation. The mechanical coupling may be rigid or elastic, simply by controlling the geometry and/or material of the stabilisation part 5s of the inner mandrel. This allows to easily control the threshold force required to reversibly separate the metal rod from the state of mechanical coupling with the ceramic element.
The invention is applicable to any ceramic element, whether it comprises through-holes or blind-holes. The use of a blind hole mechanical coupling is advantageous because it is easy to implement and isolates the metal rod from any high temperature environment in which the ceramic element is used, thus reducing the thermal requirements of the metal used for the rod. A typical example is a ceramic roller of a conveying system as illustrated in fig. 4A-4C for conveying goods through a high temperature furnace. By limiting the depth of the metal rod at both ends of the ceramic roller to a reduced length, the metal rod can be outside the high temperature zone of the furnace. Similarly, in a flow plug for controlling the flow of a metal melt flowing from a tundish, the metal rod does not necessarily reach deeper into the ceramic flow plug than the level of the metal melt, thus reducing the temperature to which it is exposed.
Thus, the invention also relates to a kit, wherein the ceramic element is a conveyor roller 1 of a conveyor system, which conveyor roller 1 is used for conveying products exposed to or at an elevated temperature of at least 200 ℃, preferably at least 500 ℃, more preferably at least 800 ℃, and wherein the insert of the rod is exposed to a temperature of at least 150 ℃, preferably at least 200 ℃, more preferably at least 300 ℃ and preferably not more than 500 ℃, more preferably not more than 400 ℃.
List of reference numerals
1: ceramic element
2: ceramic hole
4: recess of ceramic element
5: inner mandrel
5 i: insertion surface of inner mandrel
5L: locking surface of inner spindle
5 p: cylindrical proximal end of inner mandrel
6 i: longitudinal strip of inner mandrel
7: projecting member
7 b: ball as a protruding member
7 p: projection as projection member
8: outer tube
8 c: cylindrical part of the outer tube
8 i: insertion part of outer tube
8 p: extension of outer tube
9: through-hole in outer tube
10: distal end of inner mandrel
11: a frusto-conical intermediate portion of the inner mandrel sandwiched between the cylindrical proximal and distal portions of the mandrel
14: flange
58: intermediate pipe
58 s: flexible longitudinal strip of intermediate pipe
58 p: proximal end of intermediate tube
D: the diameter of the sphere is measured by the diameter of the sphere,
and Dp: height of the protrusion
X1: longitudinal axis
R2: radius of cylindrical ceramic hole
R24: the distance between the longitudinal axis X1 of the ceramic and the closed end of the recess 4
R8 b: radius of cylindrical part of outer tube hole
R8: radius of cylindrical part limited by outer tube wall
R5: radius of cylindrical proximal end of mandrel
R5L: radial dimension of locking surface of inner spindle
R5 i: radial dimension of the insertion surface of the inner spindle
R5 s: radius of the stabilizer of the inner spindle
R5 d: radius of the cylindrical distal section 10
R58 b: radius of intermediate pipe hole
P1: a transverse plane perpendicular to the longitudinal axis X1,
δ: the tolerance δ between the outer tube and the cylindrical ceramic wall is (R2-R8).
Claims (28)
1. A kit for mechanically coupling a ceramic element (1) to a rod comprising an outer surface made of metal, wherein:
(a) the ceramic element (1) comprising a cylindrical ceramic bore (2), the cylindrical ceramic bore (2) being defined by a cylindrical bore wall and extending along a longitudinal axis X1, wherein the cylindrical bore wall comprises at least one recess (4),
and wherein the rod comprises:
(b) an outer tube (8), the outer tube (8) including a protruding portion (8p) adjacent to an insertion portion (8i), and further including:
an outer tube wall made of metal and defining the outer surface of the rod, wherein a portion of the outer tube wall of the outer tube is cylindrical, extends along a tube axis from a proximal end of the projection to a distal end of the insertion portion, and has a radius R8 mating with the cylindrical ceramic hole,
an outer tube bore extending from the proximal end of the outer tube along the tube axis and extending over the entire length of the protruding portion and further over at least a part of the length of the insertion portion,
(c) at least one protruding member (7b, 7p), said at least one protruding member (7b, 7p) comprising a protruding portion having a geometry insertable into said at least one recess (4) of said ceramic element,
(d) an inner mandrel (5), the inner mandrel (5) extending along an axis and having a radial dimension suitable for insertion into the outer tube bore, wherein
(e) The insertion portion of the outer tube is insertable into the ceramic bore such that the protruding portion of the at least one protruding member engages in the at least one recess and such that the protruding portion protrudes from the ceramic element, and wherein
(f) The inner mandrel being insertable into the outer tube bore from the proximal end of the outer tube such that the protruding portion of the at least one protruding member is resiliently stabilized in the at least one recess by a stabilizing portion (5s) of the inner mandrel, and the rod is thus mechanically coupled to the ceramic element, characterized in that the outer tube is not translatable along the longitudinal axis X1 relative to the ceramic bore,
characterized in that said stabilizer (5s) of said inner mandrel (5) is radially elastic, so that said at least one protruding member (7b, 7p) can be moved out of said at least one recess (4) when a force is applied to said outer tube, said force being greater than a predetermined threshold force required for separating said rod from said ceramic element.
2. The kit according to claim 1, wherein the outer tubular bore comprises a cylindrical portion with a radius R8b and the inner mandrel (5) comprises a cylindrical portion with a radius R5 ≦ R8 b.
3. The kit of claim 2, wherein the geometry of the at least one protruding member and the at least one recess is such that when the at least one protruding member is engaged and stabilized in the at least one recess, the rod is mechanically coupled to the ceramic element such that the outer tube cannot rotate about the longitudinal axis X1 relative to the ceramic bore.
4. Kit according to claim 2 or 3, wherein the rod comprises three or more protruding members, and wherein the cylindrical bore wall comprises three or more recesses (4), and wherein the projections of the three or more recesses (4) on a transversal plane P1 perpendicular to the longitudinal axis X1 are evenly distributed on the circumference of the projection of the cylindrical ceramic bore on the transversal plane P1.
5. Kit according to claim 4, wherein said three or more recesses (4) lie in the same transverse plane perpendicular to said longitudinal axis X1.
6. Kit according to claim 2, wherein said stabilisation portion of said inner mandrel (5) has a geometry defining an elastically deformable structure.
7. A kit according to claim 6, wherein said stable portion of said inner mandrel (5) is in the shape of a hollow tube.
8. The kit according to claim 2, wherein the stabilizing portion of the inner mandrel (5) comprises an elastically deformable material.
9. The kit according to claim 2, wherein,
the at least one protruding member comprises a substantially spherical ball (7b) having a ball diameter D, and
-the insertion portion (8i) of the outer tube (8) comprises at least one circular through hole (9), the diameter of said at least one circular through hole (9) being greater than the sphere diameter D.
10. Kit according to claim 9, wherein the inner mandrel (5) comprises,
a cylindrical proximal end portion (5p), said cylindrical proximal end portion (5p) having a radius R5 and comprising said stabilizer,
a cylindrical distal end (10), the cylindrical distal end (10) having a radius R5d < R5, and
a frustoconical intermediate portion (11), said frustoconical intermediate portion (11) being sandwiched between said cylindrical proximal portion and said cylindrical distal portion, and
wherein the sphere diameter D is such that R8b < (D + R5D) < (R8+ δ), where δ is the tolerance δ between the outer tube and the cylindrical ceramic bore (R2-R8), and R2 is the radius of the cylindrical ceramic bore.
11. Kit according to claim 9, wherein the stabilizer of the inner mandrel (5) comprises at least one longitudinal strip (6i), said longitudinal strip (6i) being elastically deformable and coupled to the inner mandrel at a first and/or second end of said at least one longitudinal strip.
12. The kit of claim 11, wherein the central portion of the at least one longitudinal strip defines a radius R5s, wherein at rest R5s ≧ R5, such that D ≧ (R24-R5s), wherein R24 is the distance between the longitudinal axis X1 and the bottom of the at least one recess (4), and wherein when exposed to bending stress, the longitudinal strip can flex to reduce the radius R5s to R5s < R5.
13. The kit of claim 12, the longitudinal strip being bendable to reduce the radius R5s to at least a value R5s ≦ (R24-D).
14. Kit according to claim 2, wherein said at least one projecting member consists of a projection extending radially over a height Dp from a tip to a base, said base being rigidly coupled to a longitudinal strip of elastic flexibility forming a portion of the outer tube wall of the insertion portion (8i) of the outer tube.
15. Kit according to claim 14, wherein (Dp + R8) is comprised between 90% and 105% of R24, wherein R24 is the distance between the longitudinal axis X1 and the closed end of the at least one recess (4).
16. The kit of claim 2, wherein
The kit further comprising a middle tube (58), the middle tube (58) comprising a proximal end portion (58p), a distal end portion (58d), a middle tube wall, and a middle tube aperture (58b), wherein the distal end portion (58d) of the middle tube is insertable into the outer tube aperture from the proximal end of the outer tube,
the at least one projecting member consists of a projection extending radially over a height Dp from a tip to a base, the base being rigidly coupled to a resiliently flexible longitudinal strip forming part of the intermediate tubular wall of the distal end portion of the intermediate tube,
the insertion portion (8i) of the outer tube (8) comprises at least one circular through hole (9), the diameter of said at least one circular through hole (9) allowing the passage and engagement of said at least one protrusion therethrough, and
once the insert of the outer tube is inserted into the ceramic bore and the intermediate tube is engaged in the outer tube bore with the at least one protrusion engaged in the at least one circular through hole and in the at least one recess, the inner mandrel (5) has a diameter R5 such that it can be inserted from the proximal end (58p) of the intermediate tube (58) into the intermediate tube bore to stabilize the at least one protrusion in the at least one recess (4).
17. Kit according to claim 16, wherein (Dp + R8b) is comprised between 90% and 105% of R24, wherein R24 is the distance between the longitudinal axis X1 and the closed end of the at least one recess (4).
18. Kit according to claim 2, wherein the cylindrical ceramic bore (2) is a blind bore in the ceramic element (1).
19. The kit of claim 3, wherein the ceramic element is a conveyor roller of a conveyor system for conveying products exposed to or at an elevated temperature of at least 200 ℃, and wherein the insert of the outer tube is exposed to at least 150 ℃.
20. The kit of claim 19, wherein the conveyor system is for conveying products exposed to or at an elevated temperature of at least 500 ℃.
21. The kit of claim 19, wherein the conveyor system is for conveying products exposed to or at an elevated temperature of at least 800 ℃.
22. The kit of claim 19, wherein the insertion portion of the outer tube is exposed to at least 200 ℃ and no more than 500 ℃.
23. The kit of claim 19, wherein the insertion portion of the outer tube is exposed to at least 300 ℃ and no more than 500 ℃.
24. The kit of claim 19, wherein the insertion portion of the outer tube is exposed to at least 200 ℃ and no more than 400 ℃.
25. The kit of claim 19, wherein the insertion portion of the outer tube is exposed to at least 300 ℃ and no more than 400 ℃.
26. The kit of claim 19, wherein the insertion portion of the outer tube is exposed to a temperature of no more than 500 ℃.
27. The kit of claim 19, wherein the insert portion of the outer tube is exposed to a temperature of no more than 400 ℃.
28. A conveyor belt roller assembly for a conveyor belt system for conveying products exposed to or at an elevated temperature of at least 200 ℃, the conveyor belt roller comprising:
(a) a cylinder made of ceramic and extending along a longitudinal axis X1, the cylinder comprising a first end and a second end provided with a first and a second cylindrical ceramic bore (2), respectively, defined by a cylindrical bore wall and extending along the longitudinal axis X1, wherein the cylindrical bore wall comprises at least one recess (4),
(b) first and second rods extending along the longitudinal axis and elastically coupled to the first and second cylindrical ceramic holes (2), respectively, each of the first and second rods comprising:
(c) an outer tube (8), the outer tube (8) comprising an insertion portion (8i) inserted into a corresponding cylindrical ceramic hole, the insertion portion (8i) being adjacent to a protrusion portion (8p) protruding from the corresponding cylindrical ceramic hole, and the outer tube (8) further comprising:
an outer tube wall made of metal and defining outer surfaces of the first and second rods, wherein a portion of the outer tube wall of the outer tube is cylindrical with a radius R8 fitting the corresponding cylindrical ceramic holes,
an outer tube bore comprising a cylindrical portion of radius R8b, the outer tube bore extending from the proximal end of the outer tube along the longitudinal axis X1 and extending over the entire length of the extension portion and further extending over at least a portion of the length of the insertion portion,
(d) at least one protruding member (7b, 7p), said at least one protruding member (7b, 7p) comprising a protruding portion engaged in said at least one recess (4) of said cylindrical body,
(e) an inner mandrel (5), said inner mandrel (5) being inserted into said outer tube bore from said proximal end of said outer tube such that said protruding portion of said at least one protruding member is elastically stabilized in said at least one recess by a stabilizing portion (5s) of said inner mandrel and said first and second rods are thus mechanically coupled to said cylindrical body, said outer tube being unable to translate along said longitudinal axis X1 with respect to said corresponding cylindrical ceramic bore,
characterized in that said stabilizers (5s) of said inner mandrel (5) are radially elastic, so that said at least one protruding member (7b, 7p) can be removed from said at least one recess (4) upon application of a force onto said outer tube, said force being greater than a predetermined threshold force required for separating said first and second rods from said cylindrical body.
Applications Claiming Priority (2)
| Application Number | Priority Date | Filing Date | Title |
|---|---|---|---|
| EP17161719 | 2017-03-17 | ||
| EP17161719.4 | 2017-03-17 |
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| Publication Number | Publication Date |
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| CN108626208A CN108626208A (en) | 2018-10-09 |
| CN108626208B true CN108626208B (en) | 2021-07-16 |
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| Application Number | Title | Priority Date | Filing Date |
|---|---|---|---|
| CN201820371237.4U Active CN208560711U (en) | 2017-03-17 | 2018-03-19 | Conveyor roller component |
| CN201810225726.3A Active CN108626208B (en) | 2017-03-17 | 2018-03-19 | Kit for mechanically coupling a rod to a ceramic element |
Family Applications Before (1)
| Application Number | Title | Priority Date | Filing Date |
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| CN201820371237.4U Active CN208560711U (en) | 2017-03-17 | 2018-03-19 | Conveyor roller component |
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|---|---|
| US (1) | US11193521B2 (en) |
| EP (1) | EP3596346B1 (en) |
| JP (1) | JP7146793B2 (en) |
| CN (2) | CN208560711U (en) |
| AR (1) | AR111334A1 (en) |
| TW (1) | TWI801368B (en) |
| WO (1) | WO2018167282A1 (en) |
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| Publication number | Priority date | Publication date | Assignee | Title |
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| WO2020061260A1 (en) * | 2018-09-21 | 2020-03-26 | Glasstech, Inc | Conveyor roll end cap assembly |
| WO2020154522A1 (en) * | 2019-01-24 | 2020-07-30 | Acument Intellectual Properties, Llc | Enhanced stick fit bit design |
| CN110409075B (en) * | 2019-08-01 | 2023-09-26 | 广东白云学院 | Embroidery heightening device |
| EP4169132A1 (en) | 2020-06-19 | 2023-04-26 | Penn United Technologies, Inc. | Attachment assembly and method |
| CN112478578A (en) * | 2020-11-18 | 2021-03-12 | 吕家琦 | Plate body conveying roller body for automatic glass magnesium plate production line |
| CN114263664B (en) * | 2021-10-19 | 2022-09-13 | 大连理工大学 | High-efficient coupling mechanism who compromises to bear and thermal-insulated demand |
Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5141355A (en) * | 1989-03-22 | 1992-08-25 | Star Lock Systems, Inc. | Lock and release apparatus |
| US5370596A (en) * | 1992-05-18 | 1994-12-06 | Vesuvius Crucible Company | Ceramic and metal roll assembly |
| EP1693635A1 (en) * | 2005-02-22 | 2006-08-23 | Vesuvius Crucible Company | Ceramic conveyor roll with metal end caps and its assembly |
| CN101952085A (en) * | 2008-02-19 | 2011-01-19 | Lisi航空 | Reusable temporary fastening device for preassembling at least two previously perforated structural members |
| US20130330120A1 (en) * | 2007-08-31 | 2013-12-12 | The Blanchard Patent Holding Company, Llc | Fastener and Assembly Utilizing the Same |
Family Cites Families (13)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US3979925A (en) * | 1972-09-25 | 1976-09-14 | Taizo Kato | Shaft-coupling device preventable from over-torque transmission |
| GB1442687A (en) * | 1973-04-09 | 1976-07-14 | Ind Treuhand Ag | Conveying apparatus |
| US3942338A (en) * | 1974-03-04 | 1976-03-09 | Excel Corporation | Torque limiting coupling |
| JPS52117767U (en) * | 1976-03-03 | 1977-09-07 | ||
| US4850774A (en) * | 1987-10-26 | 1989-07-25 | The Boeing Company | Self-locking adjustable screw |
| ATE110007T1 (en) * | 1989-01-25 | 1994-09-15 | Kinematica Ag | COUPLING DEVICE, PARTICULARLY TO APPARATUS FOR DISPERSING. |
| US4900182A (en) * | 1989-03-22 | 1990-02-13 | Stillwagon Applied Techonology Incorporated | Lock and release apparatus |
| DE4324768C1 (en) | 1993-07-23 | 1994-08-25 | Labod Burkhard | Arrangement for connecting a stopper-rod for a metallurgical vessel to its lifting device, and stopper-rod suitable for the arrangement, and method for producing the arrangement |
| FR2726256B1 (en) * | 1994-10-31 | 1996-12-06 | Vesuvius France Sa | ROLLER ASSEMBLY FOR THE TRANSPORT OF HIGH TEMPERATURE ARTICLES |
| US7473049B2 (en) * | 2006-01-30 | 2009-01-06 | Hamilton Sundstrand | Ceramic-to-metal shaft assembly |
| US7914225B2 (en) * | 2007-04-05 | 2011-03-29 | Jergens, Inc. | Release pin |
| US8251606B2 (en) | 2007-08-31 | 2012-08-28 | The Blanchard Patent Holding Company, Llc | Fastener and assembly utilizing the same |
| US9677587B2 (en) * | 2011-09-21 | 2017-06-13 | Bal Seal Engineering, Inc. | Multi-latching mechanisms and related methods |
-
2018
- 2018-03-15 TW TW107108869A patent/TWI801368B/en active
- 2018-03-16 WO PCT/EP2018/056698 patent/WO2018167282A1/en active Application Filing
- 2018-03-16 EP EP18710072.2A patent/EP3596346B1/en active Active
- 2018-03-16 AR ARP180100622A patent/AR111334A1/en active IP Right Grant
- 2018-03-16 US US16/487,158 patent/US11193521B2/en active Active
- 2018-03-16 JP JP2019550611A patent/JP7146793B2/en active Active
- 2018-03-19 CN CN201820371237.4U patent/CN208560711U/en active Active
- 2018-03-19 CN CN201810225726.3A patent/CN108626208B/en active Active
Patent Citations (5)
| Publication number | Priority date | Publication date | Assignee | Title |
|---|---|---|---|---|
| US5141355A (en) * | 1989-03-22 | 1992-08-25 | Star Lock Systems, Inc. | Lock and release apparatus |
| US5370596A (en) * | 1992-05-18 | 1994-12-06 | Vesuvius Crucible Company | Ceramic and metal roll assembly |
| EP1693635A1 (en) * | 2005-02-22 | 2006-08-23 | Vesuvius Crucible Company | Ceramic conveyor roll with metal end caps and its assembly |
| US20130330120A1 (en) * | 2007-08-31 | 2013-12-12 | The Blanchard Patent Holding Company, Llc | Fastener and Assembly Utilizing the Same |
| CN101952085A (en) * | 2008-02-19 | 2011-01-19 | Lisi航空 | Reusable temporary fastening device for preassembling at least two previously perforated structural members |
Also Published As
| Publication number | Publication date |
|---|---|
| EP3596346B1 (en) | 2021-05-05 |
| EP3596346A1 (en) | 2020-01-22 |
| TW201840378A (en) | 2018-11-16 |
| CN208560711U (en) | 2019-03-01 |
| AR111334A1 (en) | 2019-07-03 |
| US11193521B2 (en) | 2021-12-07 |
| JP2020514642A (en) | 2020-05-21 |
| US20200056646A1 (en) | 2020-02-20 |
| TWI801368B (en) | 2023-05-11 |
| CN108626208A (en) | 2018-10-09 |
| WO2018167282A1 (en) | 2018-09-20 |
| JP7146793B2 (en) | 2022-10-04 |
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